Lego Lab – Balancing Equations
• Objective:
– Today I will be able to:
• Apply the law of conservation of matter to balancing
chemical equations.
• Evaluation/Assessment:
– Informal Assessment – Listening to student
interactions during the lego lab.
– Formal Assessment – Analyzing student responses
to the lego lab and the exit ticket
• Common Core Connection
–
–
–
–
Build Strong Content Knowledge
Model with mathematics
Make sense of problem and persevere in solving them
Use appropriate tools strategically
Lesson Sequence
• Evaluate: Warm – Up
• Explain: Balancing Chemical Equations Notes
• Engage and Explore: Lego balancing equations
lab
• Evaluate: Exit Ticket
Warm - Up
• For the following reaction:
– 2Na(s) + Cl2(g)  2NaCl(s)
•
•
•
•
•
Determine the reactants and products
What state is the reactant chlorine in?
What state is sodium chloride in?
What is the coefficient for sodium?
What is the subscript for chlorine?
Warm - Up
• Why do chemical equations need to be
balanced?
• Balance the following chemical equations
– Fe + O2 → Fe2O3
Objective
• Today I will be able to:
– Apply the law of conservation of matter to
balancing chemical equations.
Homework
• Complete the balancing equations practice
Agenda
•
•
•
•
•
Warm – Up
Collect Homework
Balancing Chemical Equations Notes
Lego Lab
Exit Ticket
Balancing Chemical Equations
Think back! What is the Law of
Conservation of Matter?
• Matter can not be created or destroyed, it can
be transformed from one form to another.
Why is this important for chemical
equations?
• Same number of each element on the
reactant side as the product side
• Balanced
Ms. Ose’s Tips for Balancing
Equations
• Must satisfy the law of conservation of matter
• Only use whole number coefficients
• All atoms should be present on both the
reactant and product side of the equation
• Check to see if the equation is already
balanced
• Coefficients go in front of the substance and
multiply all subscripts
Ms. Ose’s tips for balancing
equations continued
• One (1) is understood and does not have to be
written as a coefficient
• All coefficients should be reduced to lowest
terms
• Balance most complex species first and then
move to single atoms
• Double check your work!
BaS + NaCl  Na2S + BaCl2
Example 1
BaS + 2 NaCl  Na2S + BaCl2
Answer
P + O2  P 2 O5
Example 2
4P + 5O2  2P2O5
Answer
Na2O2 + H2O  NaOH+ O2
Example 3
You Try!
2Na2O2 + 2H2O  4NaOH + O2
Answer
Balancing Equation Lab
Lego Balancing Lab Directions
• Get into groups
• Travel to the stations and balance the
equations using the legos
• Each color represents a specific type of atom
• You must complete 7/10 stations. You may
pick which stations you complete
• Watch Ms. Ose’s Demo
• DO NOT THROW THE LEGOS
Exit Ticket
• Complete the lab mini - quiz